Return-path: Received: from qw-out-2122.google.com ([74.125.92.24]:31168 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754757Ab0DCQtu convert rfc822-to-8bit (ORCPT ); Sat, 3 Apr 2010 12:49:50 -0400 Received: by qw-out-2122.google.com with SMTP id 8so979426qwh.37 for ; Sat, 03 Apr 2010 09:49:50 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4BB7660A.3030900@lwfinger.net> References: <4BB7660A.3030900@lwfinger.net> Date: Sat, 3 Apr 2010 13:49:49 -0300 Message-ID: Subject: Re: RTL 8187b - naughty behaviour From: Rogerio Luz Coelho To: Larry Finger Cc: linux-wireless@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: 2010/4/3 Larry Finger : > On 04/03/2010 08:56 AM, Rogerio Luz Coelho wrote: >> Hello, sorry for posting this in a DEV list, but I tried elsewhere and >> people are generally kind, but unhelpfull. I am NOT a kernel >> programer, so I will impose on the list?s good will somewhat ;) >> >> I have a Laptop witch uses the Realtek rtl8187b chip in a USB internal >> conection. >> >> The chip WORKS in kernel Debian 2.6.32-3 , but is has an odd behavior: >> >> It works, connects and gives me ADSL speed as long as I am no more >> than 3 meters from the router. Beyond that I get a "wrong password" >> message in NetworkManager or Wicd (tried them both with similar >> results) > > Your device may behaves very differently from mine. At 15 m from my AP, > my rtl8187B device gets the following performance: > > finger@larrylap:~> tcpperf -c desktop > Duration: 10 573usec > Bytes sent: 4574208 (4467 kB 4 MB 0 GB) > Bandwidth: 3659157 b/s (3659.16 kb/s 3.66 Mb/s) > Close duration: 0s 62usec > > finger@larrylap:~> iwconfig wlan3 > wlan3 ? ? IEEE 802.11bg ?ESSID:"lwfdjf_rad" > ? ? ? ? ?Mode:Managed ?Frequency:2.412 GHz ?Access Point: 00:14:BF:85:49:FA > ? ? ? ? ?Bit Rate=11 Mb/s ? Tx-Power=20 dBm > ? ? ? ? ?Retry ?long limit:7 ? RTS thr:off ? Fragment thr:off > ? ? ? ? ?Power Management:off > ? ? ? ? ?Link Quality=69/70 ?Signal level=-41 dBm > ? ? ? ? ?Rx invalid nwid:0 ?Rx invalid crypt:0 ?Rx invalid frag:0 > ? ? ? ? ?Tx excessive retries:0 ?Invalid misc:0 ? Missed beacon:0 > > My device is a Level One WNC-0301USB and shows the following in dmesg: > > finger@larrylap:~> dmesg | grep rtl > [129918.822942] rtl8187: inconsistency between id with OEM info! > [129918.827838] phy1: hwaddr 00:11:6b:3e:c4:0a, RTL8187BvB(early) V0 + > rtl8225z2, rfkill mask 2 > [129918.860071] rtl8187: Customer ID is 0x00 > [129918.860230] Registered led device: rtl8187-phy1::radio > [129918.860333] Registered led device: rtl8187-phy1::tx > [129918.860448] Registered led device: rtl8187-phy1::rx > [129918.862425] rtl8187: wireless switch is on > [129918.863143] usbcore: registered new interface driver rtl8187 > > At my usual distance of 2 m from the AP, the transmit rate is about 13 > Mb/s and the reported signal level is -23 dBm, about what you report. > Our chips are different, but that has not previously been a problem. > > Have you used this device with kernels older than 2.6.32? Fortunately, > it does not need external firmware, thus it works with any Live CD. I > have routinely tested all fairly recent kernels and have never seen this > problem. > > Larry > I have a MS-Win7 instalation on this Laptop and it works 100% even at longer distances than you report,even with walls in between. Will do the tcpperf test as soon as I get home. There are other with the same problem with my exact chip here in Brasil , that is because one of our leading Laptop vendors uses this config. Does it matter that the USB port used in this setting is a connected to a USB HUB and then to the mother board? More details and tests will come your way in a day or two ... will reinstall Mandriva 2010 and do some tests with older kernels. Thaks for the quick reply :) Rogerio